Cashew nut shell liquid (hereinafter “CNSL”) has been known for years to contain compounds useful in various aspects of chemical industry, with particular reference to plastics production. It is of immense interest for various applications. Technical grade CNSL is a commercially available product. CNSL comprises, in major proportion (typically about 80% by weight), a material also sold separately under the trade name CARDANOL™ which is a mixture of the hydroxyalkenylphenols 3-(pentadec-8-ethyl)phenol, 3-(pentadeca-8,11-dienyl)phenol and 3-(pentadeca-8,11,14-trienyl)phenol. Minor constituents include about 18% of a material also sold separately under the trade name CARDOL™, which is a mixture of the 5-substituted resorcinols, and about 2% 2-methylcardol, which is a mixture of the corresponding 2-methyl-5-substituted resorcinols, and other materials that have not been identified.
Bisphenols are known in the art to be useful chemicals. They have been used as difunctional monomers in preparation of various polymers, such as epoxy resins, polyesters, polyethersulfones, polyetherketones, polyetherimides, polyarylates and, in particular, polycarbonates.
It is well known in the art that incorporation of a long alkyl chain in a polymer backbone imparts properties such as increase in the segmental mobility, solubility and hence it improves proccessability of the material. The use of bisphenols having long chain aliphatic substituent as a comonomer is known to offer polymer material with high flow and improved impact resistance. It is therefore of great interest and importance to synthesise new bisphenols with alkyl radical in their structure having the potential of affording polymer material with high proccessability and impact strength. It is of particular interest to develop bisphenols, which may be easily and cheaply obtained from readily available and renewable resource material such as CNSL.
The inventors herein are unaware of any prior art for preparation of the bisphenols of the structure identified above as Formula I.